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Book Review Multiple Bonds Between Metal Atoms. 2nd edition. By F. A. Cotton and R. A. Walton

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BOOKS
they describe examples of different types
of mass spectrometric systems. as well as
the most important types of photoelectron analyzers and detectors. This survey
is quite comprehensive and reasonably
up-to-date, although it would have been
useful to draw attention to the laser ionization methods that have recently become so important, by including references to relevant review articles. Also the
book does not cover methods for studying
free radicals, such as the important photoelectron spectroscopic techniques reported during the last ten years, and the use of
photodetachment spectroscopy for studying negative ions is only treated sketchily.
Despite these reservations (concerning topics that could only be treated properly in
a separate volume), this review of experimental aspects is very useful. as it provides a degree of detail and up-to-dateness
that was hitherto only accessible by reading the original literature.
The second part of the book deals with
unimolecular breakdown processes in electronically excited molecular ions. As well
as describing the most important ionization processes and showing how these can
be understood on the basis of molecular
orbital theory, the authors give special attention to the energetic aspects (breakdown curves) that are so important to the
chemist, and to ionization mechanisms. A
digression to consider the possible types
of transitions between electronic states of
molecular ions is followed by a discussion
of the energy distribution in dissociation.
Here the authors include a chapter on the
application of statistical theories of breakdown ( R R K M and QET). Although these
methods are also described in other books
and in the original literature, this chapter
is very useful, even for advanced students.
In it the authors discuss the most important points that must be considered when
using the R R K M theory. including the
choice of the transition state, effects of
nonadiabatic interactions, and numerical
methods for performing the calculations.
However, the effects of rotation and angular momentum on the reaction rate are
only treated marginally. Altogether this
chapter gives the reader a good introduction to the complexities of the theoretical
approaches that are currently available,
such as the use ofpotential surfaces derived
by a b initio methods to support R R K M
calculations.
The third part of the book is concerned
with the ‘classical’ experimental methods
of electron capture in thermal gases. The
difficulty with these methods is the poor
resolution due to the broad thermal energy
distribution, which prevents one from obtaining state-selective information. Here it
would have been useful to give a survey of
modern techniques, such as the generation of very low temperature negative ions
using an ultrasonic beam. The authors also neglect to include the important recent
work on the photodetachment of molecular and cluster anions. which yields much
more detailed information than the classical electron capture methods. Nevertheless, this part of the book summarizes the
most important mechanisms of the formation, stabilization, and energetics of negative ions in a form that will make it much
easier for the chemist to get a grasp of this
subject .
In this book the authors have succeeded
in presenting the subject of molecular ions,
which is extremely important to chemists,
in such a way that not only physical
chemists but also inorganic and organic
chemists should have sufficient background knowledge to understand it. The
reader is given a very good introduction to
the problems of this very active field of
research. The book belongs in the library
of every chemist who is concerned with
matters such as the formation, reactivity,
energetics, and kinetics of ions. It is also
attractively priced.
Kluus Miiller-Dethl<fi
Institut fur Physikalische und
Theoretische Chemie
der Technischen Universitiit Miinchen
Garching (FRG)
The Organic Chemistry of P-Lactams. Edited by G. I . Gc~irg.VCH Verlagsgesellschaft, Weinheim/VCH Publishers, New
York, 1993. XI, 381 pp., hardcover
D M 189.00.-ISBN 3-527-38 188-61156081 -083-1
Although it is 65 years since Fleming’s
momentous discovery of penicillin, research on the chemistry of the ‘enchanted
ring’ (J. C. Sheehan) is still active and
flourishing. It is therefore difficult to get a
comprehensive overview of all the recent
developments in the chemistry of p-lactams. This book aims to remedy that situation by collecting together all the most
important results achieved during the
1980s. with a few references to work published up to 1991. Instead of treating individual types of antibiotics in turn. as in
similar books on the subject, the authors
discuss methods that are of general importance.
The first chapter, “Protective Groups
in P-Lactam Chemistry” (H. Wild, 48 pp.)
goes straight into practical matters with a
survey of the special protecting group
methods used, supported by numerous
tables. The next chapter, “Introduction
and Transformation of Functional Groups
in p-Lactam Chemistry” (H. Wild, 71 pp.).
well illustrates the extent to which the lability often encountered with the four-membered ring forces one to adapt the reactions and methods to suit special situations. In “Strategies for the Synthesis of
Bicyclic [J-Lactams” (76 pp.) J. Kant and
D. G. Walker describe methods for anellating an additional ring on to the existing
p-lactam system. In the chapter entitled
p-Lactam Synthon Method: Enantiomerically Pure p-Lactams as Synthetic Intermediates” (I. Ojima, 59 pp.), we are taken
outside the usual area of antibiotics for a
description of the use of p-lactams as intermediates for the synthesis of aminoacids.
especially optically active products, and
of oligopeptides. In “Novel Methods for
the Construction of the [J-Lactam Ring“
(37 pp.) R. J. Ternansky and J. M. Morin
Jr. collect together various ring closure reactions for synthesizing p-lactams; however, the information content of this chapter falls well short of that in other treatments of p-lactam antibiotics. Lastly, the
editor and V. T. Ravikumar together report on “Stereocontrolled Ketene--1mine
Cycloaddition Reactions” as applied to
the synthesis of p-lactams (74pp.). Two
topics not covered in the book are syntheses of P-lactams by cyclocondensation of
ester-enolates with imines, and reactions
of imines with carbene complexes.
The chapters are well furnished with literature references and appear to have been
carefully checked; one error that has
slipped through appears in the formula of
Dane’s salt (p. 346). The formula diagrams have evidently been drawn by the
individual authors, and consequently they
differ in style from chapter to chapter;
however, this does not detract from the
very good visual impression given by the
book. Altogether this is a work which
contains much interesting and valuable
information for p-lactam chemists, and it
can be recommended unreservedly to everyone working in this field.
Jens Niwclzuik Emsf Schaumtrrm
Institut fur Organische Chemie
der Technischen Universitlt
Clausthal (FRG)
“
I
Multiple Bonds Between Metal Atoms.
2nd edition. By F: A . Cotton and R . A .
Walton. Oxford University Press, Oxford, 1993. 787 pp., hardcover f 70.00.-ISBN 0-1 9-855649-7
In 1994 it will be thirty years since the
crystal structure of K,Re2CI, 2 H,O was
BOOKS
determined, and the term quadruple bond
was introduced into the literature, together with the recognition that multiple
bonds between metals were experimentally accessible. In retrospect it is clear that
the occurrence of multiple bonds between
metal atoms was discovered in the most
favorable circumstances. The previous
decade had seen great advances in the understanding of the electronic structure of
transition metal compounds. the physical
methods necessary for the characterization and study of inorganic materials had
largely been developed, and finally, the
quadruple bond was first established in
the laboratory of one of the most dynamic
of modern inorganic chemists. Professor
F. A. Cotton. The model of the bonding
that was proposed in the very first publications served as a guide for further synthetic efforts. and the increasing availability of X-ray crystal structure determination as a routine tool allowed rapid
and unambiguous characterization of the
compounds. The subject has developed
rapidly, but coherently, to become a
paradigm of modern descriptive chemistry. Many high yield syntheses of these
multiply bonded compounds are now
available. and the bonding exotica of
twenty-five years ago have become the
readily available starting materials of
today. There have, of course, been
many surprises in this development.
not least in the number of multiply
bonded species that may be prepared
for a wide variety of transition metals.
The extraordinary reactivity of the
metal-metal multiple bond (shown for
example by the rapid breaking of the
carbon-carbon triple bond on reaction of alkynes with W,(OR),. or the
dissociation of the chromium-chromium
quadrupole bond of [Cr,(02CCH,),]
in aqueous solution) was hardly predictable.
The continuing interest in this remarkable chemistry has led the authors to produce a second edition of the book they
originally published in 1982. The activity
during the ten years following its publication was such that the second edition is
70% longer than the first. It comprehensively covers the literature up to 1990,
with moat of 1992 and some papers of
early 1992. After a brief historical introduction, the greater part of the book discusses the compounds according to the
metals involved: dirhenium and ditechnetium compounds (1 11 pp.), dimolybdenuin and ditungsten compounds
(1 19 pp.), excluding the L,M-ML, compounds which are treated in a separate
chapter (96 pp.). dichromium compounds
(45 pp.), diruthenium and diosmium com-
pounds (32 pp.), dirhodium compounds
(71 pp.), other dimetal compounds
(31 pp.), and metal-metal multiple bonds
in other contexts (97 pp.). Each chapter is
logically subdivided according to metal
type, metal oxidation state, and ligand
type. The text is extremely well presented,
with abundant use of tables, figures, and
structural formulas. In contrast to this element by element approach, Chapter 10
discusses physical, spectroscopic, and
theoretical results for all compounds. and
thereby gives a more comparative view. It
shows not only the power of modern
physical methods, but also the limitations
and difficulties of interpretation associated with the methods, be they experimental
or theoretical. It is piquant to note that it
is easier to measure the metal-metal vibrational frequencies in the first excited
state than to make a reasonably accurate
(f10%) estimate of the metal-metal
bond energy. Finally, Chapter 11 gives a
brief coverage of the literature of late 1991
and early 1992. The chapter lengths given
above show clearly how metals of
Groups 6 and 7 still occupy a dominating
position in this field, quite logically since
they are most easily obtained in the d3
and d4 configurations so well suited for
metal-metal multiple bonding. This reviewer was, however, struck by the relative paucity of mechanistic studies involving the classical L,MML, systems in
comparison with the abundance of
reactivity studies for L,M=ML, compounds.
The authors are to be thanked for undertaking the arduous task of assembling
the data from over 2000 research papers
into a critical and comprehensive book.
and should be congratulated on their success. As in the case of the first edition,
this book will become the standard reference and an essential tool for anyone
working in the field. However, this
book is too good to leave to specialists
alone. The introductory chapter could be
read with pleasure and profit by any advanced undergraduate, and the chapter
on physical, spectroscopic, and theoretical results. while it may require some
cross-references to earlier chapters, is a
model of clear exposition and critical
examination of results which should interest all inorganic chemists. This book gives
a masterly description of one of the most
active areas of modern inorganic chemistry, and will serve not only as a reference, but as a stimulus for further research.
Alun E Williams
Department of Inorganic, Applied and
Analytical Chemistry
University of Geneva (Switzerland)
Kinetic Theory and Irreversible Thermodynamics. By B. C. Eu. Wiley, Chichester,
1992. 732 pp., hardcover f 67.00.
ISBN 0-471-61 524-2
The thermodynamics of irreversible
processes close to equilibrium is now a
well-established area of physics and physical chemistry. In order to calculate the
increase in entropy resulting from an irreversible process, one assumes that a local
thermodynamic equilibrium is established. The flows and the thermodynamic
forces driving them are related by appropriately chosen linear equations, in which
the reciprocity condition of Onsager and
the Curie principle play an important role.
The range over which the linear equations
are valid must be determined experimentally.
However, irreversible processes also
take place under conditions such that the
system under observation is far removed
from equilibrium and the linear equations
are no longer applicable. The theoretical
treatment of such processes raises a number of fundamental questions which must
be answered before one can attempt to
formulate a consistent theory of irreversible processes remote from equilibrium. This monograph is a contribution
towards the development of an appropriately extended form of irreversible thermodynamics. The author considers irreversible kinetic equations such as the
Boltzmann equation as fundamental relationships that are based on the microscopic equations of motion of particles. The
irreversible kinetic equations are used to
describe the behavior of macroscopic systems (gases, liquids, etc.). Based on the
theory of irreversible processes, methods
of solution are developed which are
consistent with the laws of thermodynamics.
The book is divided into fifteen chapters. The continuum theory and the thermodynamics of irreversible processes (including a chapter on irreversible processes
in electromagnetic fields) are treated in
Chapters 2 to 9, then the kinetic theory
and the statistical-mechanical basis of irreversible thermodynamics remote from
equilibrium are treated in Chapters 10
to 15.
The book is intended for physicists and
chemists with interests in this area of theory, and can be recommended for reading
by everyone who wishes to learn about the
current situation in the development of an
extended thermodynamic theory of irreversible processes.
Dietrid1 Woermunn
Institut fur Physikalische Chemie
der Universitiit Koln (FRG)
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